Do you think she likes me?

In my opinion she likes you. She seems to be flirty with you, and she texts you a lot which means that she wants to be in contact with you as much as possible. She's interested to know if you're single which is a good sign as well, as she might want to get together with you. Just because she has a long term friend who's a guy doesn't mean that she isn't interested in you. Maybe when she sees you in the halls, she's a bit shy, or she's busy or lost in thought...there's any number of possibilities. But overall, the signs point to her liking you.